Topic: Need help with oil!

[greenninja85]

I've been working on rebuilding a 1978 cb750f engine for a little while now.  I wanted to figure out which oil I was going to be running in it before I got it back together.  I had originally planned on running full synthetic mobil 1 10w 40 since thats what i've always ran in my newer bikes with good luck.  I was then told by hondaman not to run a full synthetic or 10w40 in a cb750 to go with a 20w50 mineral based oil.  So I got some bel-rays 20w50 and was feeling good about that...until I got my new cam to put in the engine and in the instructions for it it says to use a sae 30 petroleum based oil.  I'm not sure what the difference is between mineral based and petroleum based and don't want to skrew anything up by not using that.  So i'm not sure which I should go with   Any ideas from people who have maybe put a bigger cam in or anything would help. 

[goldarrow]

I didn't think we are due for oil thread so soon!  Dave, easy on this one ok?!?!

[greenninja85]

haha ya i'm not trying to start a debate on which kind of oil is the best.  I know everyone has a certain kind they trust, i'm just more interested in knowing if I should go with what I was told to use for the engine or what this new cam is telling me to use.  Or if either would be fine.  I would think what hondaman told me to use would be good even with this cam.  Just wanted some opinions to make me feel more at ease

[goldarrow]

I have Mobil 1 full synthetic 10w40 in my bike, so far 400+ miles since the top end rebuilt and still good.  Should have used cheaper oil for break-in but didn't feel like going to store and buy more oil at the time.  Going to do 1st oil change once hit about 500 miles.  I have 650 cam on the 550 engine. 

And the bike has been running great